Albert Barnes Commentary 1 Chronicles 11:26

"Also the mighty men of the armies: Asahel the brother of Joab, Elhanan the son of Dodo of Beth-lehem," — 1 Chronicles 11:26 (ASV)

The list of names given here generally corresponds with the one in 2 Samuel 23:24–39, but it presents several remarkable differences.

1. The number of names in Chronicles is 47, while the number in Samuel is 31.
2. Four names in the list from Chronicles are not in Samuel.
3. Five names in Samuel are not in Chronicles.
4. Many of the other names, both personal and local, vary between the two lists.

It is quite possible that the two lists varied to some extent from the beginning. The writer of Chronicles distinctly states that he gives the list as it stood when David became king over all Israel (1 Chronicles 11:10). The writer of Samuel, however, does not assign his list to any specific period of David’s reign but probably presents it as it was composed at a later date.

Therefore, it is quite possible that the names found only in Chronicles belong to men who had died or left the army before the other list was compiled. Consequently, the new names in Samuel would be those of the men who had taken their places. See the note on 2 Samuel 23:39.